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PubMed1988

Monoclonal antibodies for progesterone receptor assays and polymorphism studies in breast cancer. Comparison with radioligand assays.

Progesterone receptors (PR) from human breast tumors were assayed by a new method using monoclonal antibodies immobilized on beads (PR-EIA, Abbott Laboratories). EIA results were compared to those obtained with the dextran-coated charcoal method using a tritiated ligand (ORG 2058). The precision and reproducibility of the EIA method were studied over a 3-month period: intra-assay coefficients of variation were less than 6% for the range of the assay (between 5-250 fmol/ml), and inter-assay coefficients of variation calculated on 13 consecutive standard curves were less than 10%, except for standard 0 (33%). PR assays performed on 78 tumors both by EIA and radioligand (RLA) were compared. The linear regression obtained was: PR-EIA = 0.81 RLA+1 fmol/mg protein (r = 0.88). For reproducibility studies, cytosols were assayed twice during a period ranging from 1 week-3 months, both by EIA and RLA. The linear regression obtained between the second assay (B) and the first assay (A) was: B = 0.98 A + 11 fmol/mg protein for RLA (r = 0.98), and B = 0.99 A-7 fmol/mg protein for EIA (r = 0.98). To study the effect of KCl on PR-EIA, 26 tumors were homogenized in 0.4 M KCl Tris buffer and assayed both by EIA and RLA. A good correlation was obtained between the 2 methods, but higher values were obtained with PR-EIA (P = 1.6) in comparison with RLA. The addition of KCl to the cytosol showed that KCl had no effect on EIA results, but significantly lowered RLA results. To study the effect of KCl on progesterone receptor isoforms, cytosols were analyzed by chromatography on TSK G3000 SW columns, and the presence of PR was detected in each fraction by both EIA and RLA. In the absence of KCl, only the oligomeric form of PR was observed; however with both techniques, detection of this form different from tumor to tumor, emphasizing the inter-tumoral molecular heterogeneity of PR. After PR isoform dissociation by KCl (0.4 M) and chromatographic analysis of the forms obtained, monoclonal antibodies detected PR molecular forms different from those observed by radioligand; furthermore, chromatographic patterns obtained were different from one tumor to another and confirmed the inter-tumoral molecular heterogeneity of the progesterone receptor.

Antibodies, Monoclonal↗
PubMed1988

[Assessment of the response of human bladder cancer cell lines to radiation using colony formation assay and [3H] thymidine incorporation assay].

The effect of radiation on the human bladder cancer cell lines, KK47 and J82, was studied using colony formation assay and [3H] thymidine incorporation assay. The response to radiation was dose-related for both assays, but the curve for the colony formation assay was steeper than that for [3H] thymidine incorporation assay. However, the steepness of the curve for [3H] thymidine incorporation assay increased to be approximately the same as that for the colony formation assay as the incubation period increased. [3H] Thymidine incorporation assay can provide a rapid assessment of radiation sensitivity comparable to that obtained by the colony formation assay to select a radiosensitive bladder cancer patient for definitive or adjunctive radiotherapy.

Cell Line↗
PubMed1984

Amikacin assay: correlation between rapid bioassay, enzyme immuno-assay (EMIT) and fluoro-immuno-assay (FIA).

Three methods (rapid bioassay, enzyme immunoassay and fluoroimmunoassay) for the determination of amikacin level in serum are compared. The statistical analysis of the results show correlation coefficients equal to 0.967 (EMIT versus FIA), 0.970 (bioassay versus FIA) and 0.983 (bioassay versus EMIT). The three methods are acceptable for routine clinical use. The enzyme immunoassay adapted on a centrifugal analyzer appears to be a method of choice for laboratories with a large workload. However, the rapid bioassay described in this paper remains adequate for laboratories testing 5 to 10 sera per day.

Amikacin↗
PubMed1995

Quantification of mitogen induced human lymphocyte proliferation: comparison of alamarBlue assay to 3H-thymidine incorporation assay.

Proliferation of human lymphocytes in response to various stimuli has traditionally been assessed by measuring uptake of radiolabeled nucleotides such as 3H-thymidine. We have evaluated a fluorometric assay, which uses the commercially available reagent, alamarBlue, as a potential substitute for the 3H-thymidine assay in measuring proliferation of human lymphocytes. In this assay, alamarBlue is added to a population of cells where it is reduced by mitochondrial enzyme activity. The reduced form of the reagent is fluorescent and can be quantitatively detected. The safety and convenience of the alamarBlue assay make it very attractive for use in the clinical laboratory. In this study peripheral blood mononuclear cells (PBMC) from healthy donors were stimulated using the mitogen Concanavalin A, and proliferation was assessed using either the 3H-thymidine or the alamarBlue assay. The alamarBlue assay reliably detects human PBMC and we found that the linear range of detection was 10(4) cells/well (96-well plate) to 5 x 10(5) cells/well. Detection of human PBMC is highly reproducible and the alamarBlue assay may be suitable in a number of applications where detection or relative quantitation of human PBMC is required. The alamarBlue assay also detected mitogen induced proliferation of PBMC although with a significantly lower level of sensitivity than the standard 3H-thymidine assay.

Cell Count↗
PubMed1997

Measurement of nitrite and nitrate in biological fluids by gas chromatography-mass spectrometry and by the Griess assay: problems with the Griess assay--solutions by gas chromatography-mass spectrometry.

Assay methods based on the Griess reaction are frequently used to measure nitrite and nitrate in urine, plasma, and other biological fluids. With minor exceptions, careful attention has not been paid in extending the Griess assay from aqueous solutions to biological fluids, In the present study, parallel measurements of nitrite and nitrate were performed in urine, plasma, and aqueous solutions with a published batch assay based on the Griess reaction and with gas chromatography-mass spectrometry (GC-MS). We report here further interferences by free reduced thiols, proteins, and other plasma constituents in the Griess assay but not in GC-MS. The best correlation (r2 = 0.985) between the Griess assay and GC-MS was observed for aqueous solutions in the absence of thiols. Unlike GC-MS, the Griess assay was not applicable to whole human plasma and urine samples. For the measurement of nitrate in diluted human urine samples, reduction by cadmium was performed both under acidic (pH 2 or 5) and alkaline (pH 8.8) conditions. The mean recovery rate of nitrate from urine samples was quantitative in the GC-MS but amounted to only 30-80% in the Griess assay. Measurement of nitrate in human urine samples (n = 33) resulted in an excellent correlation between two GC-MS techniques (r2 = 0.979) but only in a poor correlation (r2 < 0.64) between the Griess assay and GC-MS. Unlike GC-MS, the batch Griess assay is associated with many problems in measuring nitrate in biological fluids.

Chromatography, High Pressure Liquid↗
PubMed1994

MTT-assay and neutral red release (NRR)-assay: relative role in the prediction of the irritancy potential of surfactants.

A comparative study on the in vitro and in vivo irritancy of anionic, amphoteric and non-ionic surfactants was performed. In vitro ED50 values of the surfactants were determined by two cytotoxicity assays, the dimethylthiazoldiphenyltetrazoliumbromide (MTT) assay and the neutral red release (NRR) assay on serum-free cultured human foreskin keratinocytes. In vivo human irritancy data were obtained by a 24 hour occlusive patch test in volunteers and the irritant skin response quantified by visual scoring, evaporimetry and colorimetry. A close relationship between the evaluation methods of the patch test was observed (r = 0.92 to r = 0.96), confirming that the 'bioengineering' methods, such as evaporimetry and colorimetry are suitable for measuring skin irritation. For six surfactants evaluated we found a good correlation (r = 0.91) between the ED50 values of the MTT assay and the in vivo irritancy data. The NRR assay yielded less satisfactory correlation coefficients with regard to MTT assay (r = 0.42) and in vivo irritancy data (r = 0.46). This can be mainly attributed to a misinterpretation of the amphoteric and non-ionic surfactants by the NRR assay. While the NRR assay may better evaluate the anionic surfactants, the MTT assay seems to be more suitable when testing a broader range of chemically diverse surfactants. Limitations of cell culture systems are noted, although the potential usefulness of cultured human skin cells for skin irritancy testing has been clearly demonstrated.

Adult↗
PubMed2002

Comparison of reporter gene assay and immature rat uterotrophic assay of twenty-three chemicals.

We performed a reporter gene assay for ERalpha-mediated transcriptional activation and an immature rat uterotrophic assay of 23 chemicals, to study the relationship between these two assays and to examine the usefulness of the reporter gene assay. The chemicals analyzed in the study were as follows: benzophenone, bisphenol A, bisphenol B, bisphenol F, p-cumyl phenol, dibutyl phthalate, dicyclohexylphthalate, dihydrotestosterone, equilin, 17alpha-estradiol, estrone, ethynyl estradiol, genistein, hematoxylin, nonylphenol mixture, 4-n-nonylphenol, norethindrone, norgestrel, octachlorostyrene, 4-n-octylphenol, 4-tert-octylphenol, tributyltin-chloride and zearalenone. To perform the reporter gene assay, HeLa cells were transfected with a rat ERalpha expression construct and an estrogen-regulated luciferase reporter construct. The transcriptional activities of each chemical were tested over concentrations ranging from 10 pM to 10 microM and the EC50, PC50 and PC10 values were calculated. In the immature rat uterotrophic assay, the doses of 21 chemicals, with the exception of dibutyl phthalate and ethynyl estradiol, were 0, 2, 20 and 200 mg/kg; each group consisted of six rats. The doses of dibutyl phthalate and ethynyl estradiol were 0, 40, 200 and 1000 mg/kg per day and 0, 0.2, 2 and 20 microg/kg per day, respectively. In the reporter gene assay, the PC10 values were calculated for 15 chemicals: bisphenol A, bisphenol B, bisphenol F, p-cumyl phenol, dihydrotestosterone, equilin, 17alpha-estradiol, estrone, ethynyl estradiol, genistein, nonylphenol mixture, norethindrone, norgestrel, 4-tert-octylphenol and zearalenone. These chemicals corresponded to the chemicals that tested positive in the uterotrophic assay. The other chemicals were negative in the reporter and uterotrophic assays. Although the EC50 and PC50 values could only be calculated for five and six chemicals, respectively, the PC10 values were shown to be well correlated with the EC50 values by a correlation analysis (R(2)=0.9202). These findings demonstrate that PC10 values are preferable to EC50 and PC50 values for predicting the estrogenic activities of chemicals.

Animals↗
PubMed2003

Comparison of the reporter gene assay for ER-alpha antagonists with the immature rat uterotrophic assay of 10 chemicals.

We performed a reporter gene assay for estrogen receptor (ER)-alpha agonists and antagonists of 10 chemicals that showed both estrogen agonistic and reduced the estrogenic effect of ethinyl estradiol in a rat uterotrophic assay. The chemicals tested by the immature uterotrophic assay were p-(tert-pentyl)phenol, 4,4'-thiobis-phenol, 4,4'-(hexafluoroisopropylidene)diphenol, 2,2-bis(4-hydroxyphenyl)-4-methyl-n-pentane, 4,4'-(octahydro-4,7-methano-5H-inden-5-ylidene)bisphenol, 4-(phenylmethyl)phenol, 4,4'-dihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 4-hydroxybenzophenone and 2,4,4'-trihydroxybenzophenone. Although all chemicals examined in this study were positive in the reporter gene assay for ER-alpha agonists, 4,4'-(octahydro-4,7-methano-5H-inden-5-ylidene)bisphenol was only positive in the reporter gene assay for ER-alpha antagonists. These findings demonstrate that results of the reporter gene assay for ER-alpha agonists correlated well with those of the uterotrophic assay, but antagonistic change of 9 of 10 chemicals in the uterotrophic assay was not detected by the reporter gene assay for ER-alpha antagonists.

Animals↗
PubMed1996

Evaluation of a tissue factor dependent factor V assay to detect factor V Leiden: demonstration of high sensitivity and specificity for a generally applicable assay for activated protein C resistance.

Resistance to the anticoagulant effects of activated protein C (APC) is now considered the most prevalent cause of inherited thrombophilia. The great majority of patients with activated protein C resistance (APCR) have a missense mutation in the factor V molecule (factor V Leiden, FVR506Q) resulting in defective inactivation of factor Va due to a loss of an APC cleavage site. The diagnosis of APCR has been based upon the inability of APC to prolong the activated partial thromboplastin (aPTT) clotting time in subjects with APCR. However, this assay has a number of deficiencies which limit its general use. We have evaluated a newly described one-stage tissue factor dependent factor V coagulation assay for APCR in 117 patients and controls and compared the results of this assay in a blinded manner to a polymerase chain reaction (PCR) based assay for the molecular defect of factor V Leiden. 43% (50/117) of the patients studied were receiving coumadin or heparin, or had a lupus anticoagulant. The tissue factor dependent factor V assay had 100% specificity and sensitivity for factor V Leiden and successfully predicted a homozygous state in the three documented homozygotes. The PCR-based assay for factor V Leiden resulted in a single false positive assay due to a silent A to C transition at nucleotide 1692 resulting in the loss of the Mnl restriction endonuclease cleavage site. The single-stage tissue factor dependent factor V assay is a highly sensitive and generally applicable assay for APCR.

Blood Coagulation Tests↗
PubMed2002

A blinded in vitro study with Refacto mock plasma samples: similar FVIII results between the chromogenic assay and a one-stage assay when using a higher cephalin dilution.

Assay of factor VIII (FVIII) in patient samples is routinely carried out using the one-stage assay rather than the chromogenic substrate assay. The introduction of new FVIII preparations for the treatment of haemophilia A, including immunopurified FVIII and particularly, recombinant FVIII (rFVIII) concentrates, has led to discrepancies between the results obtained with the two assays. In patients treated with rFVIII concentrates, FVIII levels measured with the one-stage assay can be 20-50% lower than those measured with the chromogenic assay. In this study, the one-stage assay was performed with cephalin dilutions higher than those recommended by the manufacturer. B-domain-deleted recombinant FVIII, Refacto, was diluted to eight different concentrations, ranging from 1-100 IU dL(-1), in FVIII-deficient plasma and the FVIII activity of the eight solutions was determined by the chromogenic method in a central laboratory. Aliquots were then assayed by the one-stage method in the four participating laboratories, using different dilutions of CK-Prest. When CK-Prest was reconstituted according to the manufacturer's recommendations (dilution 1 : 1), the difference between the one-stage and chromogenic methods was close to 30%. CK-Prest cephalin dilutions of 1 : 5 and 1 : 8 gave very similar results with the two methods, without increasing the interlaboratory coefficient of variation. These findings confirm the influence of phospholipids on the one-stage assay, particularly the importance of using a phospholipid concentration close to the physiological value in platelets. This modified one-stage method may therefore offer an alternative to the use of a concentrate-specific standard.

Chromogenic Compounds↗
PubMed2002

The Ultegra rapid platelet-function assay: comparison to standard platelet function assays in patients undergoing percutaneous coronary intervention with abciximab therapy.

BACKGROUND: Despite the proven benefit of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention, significant interpatient variability exists in antiplatelet response. Furthermore, a diminished degree of platelet inhibition is an independent predictor of adverse cardiac events, highlighting the need for accurate and precise monitoring of platelet function. METHODS: Patients (n = 192) who underwent elective percutaneous coronary intervention at 4 centers were enrolled. The following 3 time points were studied: 1, baseline, before abciximab bolus administration; 2, during, within 1 hour of abciximab bolus administration; and 3, post, 24 hours after abciximab bolus administration or at the time of patient discharge, whichever occurred first. The following 3 assays were compared at all time points: Ultegra rapid platelet-function assay (Ultegra RPFA), conventional turbidometric platelet aggregometry, and receptor binding assay with [125I]-abciximab. Variability in Ultegra RPFA measurements between operators was determined with performance of the assays at the point of care and in the laboratory. A sub-study of 22 patients at 1 center was performed in which the laboratory scientist performed all 3 assays in duplicate at each time point. RESULTS: Comparison with the receptor binding assay and conventional platelet aggregometry in 120 patients showed that the Ultegra RPFA correlated with aggregometry (r = 0.89) and with the receptor binding assay (r = 0.89). There was good agreement (r = 0.80) between values obtained by intended users and those obtained by laboratory scientists. Furthermore, Ultegra RPFA values had equivalent precision to the standard assays. CONCLUSION: The Ultegra RPFA has equivalent accuracy and precision when compared with the 2 reference assays studied. Ultegra RPFA measurements are not operator-dependent and are not influenced by concomitant medications, hematologic parameters, or demographics.

Abciximab↗
PubMed2001

Evaluation of the new ImmuliteTurbo cTnI assay and the original immulite cTnI assay.

OBJECTIVES: An analytical and clinical evaluation of cTnI on the ImmuliteTurbo system with 15 min assay time compared to 45 min with the original Immulite assay is presented. METHODS AND DESIGN: Detection limit, functional sensitivity, AMI decision limit, assay linearity, influence of sample material (serum, heparin, citrate and EDTA plasma), interference, analytical and clinical method comparison studies were performed. RESULTS: Functional sensitivity (at CV 20%) was 0.35 compared to 0.23 microg/L for the original assay. AMI decision limit (99th percentile of a reference control group) was 0.48 microg/L for both assays. In patients with acute coronary syndromes, chronic renal failure or pulmonary embolism the assays showed concordant results in 87.2-96.5%. Differing results were only found around the cut-off level and were attributed to assay imprecision. CONCLUSION: The new assay is sensitive for the determination of cTnI, shows comparable results to the original assay version and is easy to perform within 15 min.

Adolescent↗
PubMed2006

Telomerase activity determined by conventional telomeric repeat amplification protocol and reverse transcriptase-polymerase chain reaction assay in ovarian lesions: a comparison of assays.

OBJECTIVE: Telomerase is capable of restoring telomeric sequence lost during replication. No or low levels of telomerase activity are present in normal somatic cells, whereas up to 85-90% of all cancer cells express telomerase activity, suggesting telomerase as a possible tumor marker. The catalytic subunit, hTERT, correlates with the activity of the enzyme. MATERIAL AND METHODS: Telomerase activity in ovarian tissue was measured by the functional telomeric repeat amplification protocol (TRAP)eze assay, and a quantitative reverse-transcriptase-polymerase chain reaction (RT-PCR) assay measuring the expression of the telomerase catalytic subunit, hTERT. RESULTS: A weakly positive correlation was found between telomerase activity and severity of ovarian disease using the results of the TRAP assay, compared to a strongly positive correlation considering the results obtained in the RT-PCR assay. A statistically significant difference between the benign and borderline groups was present using the RT-PCR assay, allowing for screening for both borderline and primary malignant conditions with a specificity of 97% and a sensitivity of 68%. No significant statistical difference was found between telomerase activity in benign and borderline conditions when using the TRAP assay. When screening for primary malignancy, the specificity and sensitivity rates were 94% and 21%, respectively. CONCLUSIONS: The RT-PCR assay allowed discrimination between benign and borderline and malignant cases, and thereby proved superior to the TRAP assay, which could not discriminate the benign cases from the borderline cases. This suggests that the RT-PCR assay may be useful in screening for both borderline and primary malignancy in ovarian lesions.

Biomarkers, Tumor↗
PubMed1995

Comparison of characteristics of Q beta replicase-amplified assay with competitive PCR assay for Chlamydia trachomatis.

In order to study infections due to Chlamydia trachomatis, we have compared semiquantitative PCR and Q beta replicase-amplified assays for detection of this organism. The PCR assay was directed against the C. trachomatis 16S rRNA gene. Quantitation was accomplished by adding known amounts of a plasmid containing a truncated segment of the 16S rRNA gene target to chlamydia-containing samples and then amplifying with a common primer set. The Q beta replicase assay consisted of reversible target capture of C. trachomatis 16S rRNA, which was followed by amplification of an RNA detector probe in the presence of the enzyme Q beta replicase. In a clinical matrix, the lower limit of detection of both the PCR and Q beta replicase assays was five elementary bodies. The Q beta replicase and PCR assays were quantitative over 10,000- and 1,000-fold ranges of organisms, respectively. Analysis of the effects of endocervical matrix on amplification was accomplished by examining 94 endocervical specimens by each technique. Both assays detected five of six culture-confirmed specimens as well as three culture-negative specimens. PCR inhibitors were detected in 13 specimens. The Q beta replicase assay, in contrast, showed no evidence of sample inhibition. The Q beta replicase and PCR assays should allow quantitative investigation of infections due to C. trachomatis. In addition, because it targets highly labile RNA, the Q beta replicase assay may facilitate investigations into the role of active persisting infection in culture-negative inflammatory conditions.

Base Sequence↗
PubMed2002

Comparison of three commercially available peptide-based immunoglobulin G (IgG) and IgA assays to microimmunofluorescence assay for detection of Chlamydia trachomatis antibodies.

Three commercially available, peptide-based enzyme-linked immunosorbent assay (ELISA) systems (Chlamydia trachomatis IgG and IgA EIA [CT-EIA; Labsystems OY, Helsinki, Finland], SeroCT IgG and IgA [SeroCT; Savyon Diagnostics Ltd., Ashdod, Israel], and Chlamydia trachomatis IgG and IgA pELISA [CT pELISA; Medac, Wedel, Germany]) were evaluated for the detection of serum immunoglobulin G (IgG) and IgA antibodies specific for Chlamydia trachomatis and compared to the "gold standard" assay, the microimmunofluorescence (MIF) assay. Serological responses were analyzed in 149 women aged 20 to 30 years. Cervical swabs obtained from these women were examined for C. trachomatis by PCR, and 43 were found to be positive. The overall seroprevalence rates detected by CT-EIA, SeroCT, CT pELISA, and the MIF assay were 42, 42, 35, and 39%, respectively, for IgG and 7, 7, 3, and 7%, respectively, for IgA. The IgG seroprevalence rates for the PCR-positive women were two to three times higher than those for the PCR-negative women, i.e., 72 versus 29%, 72 versus 29%, 47 versus 26%, and 74 versus 25% for CT-EIA, SeroCT, CT pELISA, and the MIF assay, respectively. After discrepancy analysis, the sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the IgG assays; for CT-EIA they were 84.7, 98.6, 98.4, and 86.7%, respectively; for CT pELISA they were 71.4, 97.3, 96.2, and 78.3%, respectively; for SeroCT they were 84.7, 98.6, 98.4, and 86.3%, respectively; and for the MIF assay they were 79.2, 83.1, 98.3, and 83.1%, respectively. In conclusion, these peptide-based ELISA systems for the serological detection of C. trachomatis infection performed as well as the MIF assay. Since these tests are less time-consuming, less expensive, and easier to perform than the MIF assay, they might be useful in the serodiagnosis of chlamydial infection.

Adult↗
PubMed2003

Comparison of a new quantitative ompA-based real-Time PCR TaqMan assay for detection of Chlamydia pneumoniae DNA in respiratory specimens with four conventional PCR assays.

Chlamydia pneumoniae, an important respiratory pathogen, is difficult to culture, and detection rates by conventional PCRs vary considerably. A new quantitative ompA-based real-time PCR assay based on TaqMan technology for detection of C. pneumoniae in respiratory samples is described, and its performance in terms of sensitivity and reproducibility is compared with those of four published conventional PCRs (one single-step PCR targeting a cloned PstI fragment; two nested PCRs, one targeting the 16S rRNA gene followed by hybridization and the other targeting the ompA gene; and a touchdown enzyme time-release [TETR] PCR also targeting the 16S rRNA gene). Both ompA-based PCRs showed the best analytical sensitivity. All five assays could detect even lower target levels from spiked sputum, with the 16S rRNA assays performing better than the ompA-based nested PCR (10(-6) inclusion-forming units [IFU] were detected in four of four and two of four replicates by the 16S rRNA TETR PCR and the 16S rRNA nested PCR, respectively). In general, the ompA-based real-time protocol produced the most consistent positive results for all replicates tested down to 10(-6) IFU. Eight of 45 patient sputum specimens (18%) were C. pneumoniae DNA positive in at least one of four replicates tested by at least one assay. Without taking into consideration the analytical sensitivity or the reproducibility of the test results, the numbers of C. pneumoniae DNA-positive sputum specimens (n = 8) were four, three, two, two, and one for the 16S rRNA TETR assay, the PstI-based single-step PCR, the ompA-based real-time PCR, the ompA-based nested touchdown PCR, and the 16S rRNA-based nested PCR, respectively. However, the overall rate of concordance of positive results was low. Only one cell culture-positive sputum specimen was positive by four of five assays (14 of 16 replicates; mean cycle threshold value, 25; 10(8) particles/ml of sputum). Thirty-seven specimens were C. pneumoniae negative by all five assays for all replicates tested, as were all negative controls (n = 65 to 100 per testing panel). No PCR inhibitors were detected by real-time PCR or by the 16S rRNA-based nested assay. We confirm that the analytical sensitivity of an assay for the detection of C. pneumoniae does not necessarily predict its ability to detect its target in sputum. A quantitative, fast, and easy-to-handle diagnostic approach such as the ompA-based real-time TaqMan PCR described here might improve the detection of C. pneumoniae in respiratory samples.

Adult↗